1. Field of Invention
The present invention relates to data storage technology. More particularly, the present invention relates to a memory device.
2. Description of Related Art
Memory modules like double data rate (DDR) synchronous dynamic random access memory (SDRAM) are a class of memory capable of providing approximately twice the bandwidth of single data rate SDRAM. DDR SDRAM achieves this increased bandwidth without requiring an increased clock frequency by transferring data on both rising and falling edges of a clock signal. Therefore, the DDR SDRAM is often used in the design of integrated circuits.
In a typical memory device mentioned above, the data is transmitted by utilizing data signal DQ and data strobe signal DQS. However, the path for transmitting the data signal and the path for transmitting the data strobe signal induce variable latencies. It is not easy for the data latching circuit to latch the signal at the right timing when there is difference between the arrival of the data signal and the data strobe signal.
Accordingly, what is needed is a memory device to address the issues mentioned above.